no it isn't and no it doesn't. All natural languages carry a large portion of ambiguity, to the extend that Steven Pinker even count ambiguity as a defining factor of natural language!
You raise an interesting question as to whether the language can be separated from the culture. I'd wager that there's a ton of imprecision in Asian languages due to culture where a lot of communication is unspoken and relies on context. Korean-Canadian working as a manager in China and finding that I don't know how to communicate with my team even after 1.5 years on the job. Part of it is that I suck at being a manager, but part of it is that my team expects me to be able to read their minds. Chinese people tell me that the normal thing is to say something and mean something else.
If you separate language room the goal of communication and the context of culture, it's easy to analyze language differences the way you would analyze the difference between Python and Swift. But that analysis may not be so useful or applicable in day-to-day life.
What is your point exactly? How does that joke in anyway counter the point that ambiguity is a prominent feature in all languages? do you honestly believe that because this joke doesn't translate, there can't possibly exist jokes based on double entendre or other ambiguities in the target language?
Chinese is more full of double (or more) meanings than any other language I've studied. Chinese literature and poetry are famous for playing on multiple meanings of a single character or sound.
Even in my one year of Chinese, I learned a great appreciation for the ridiculous puns that can be made in Chinese. It's also remarkably concise. I think most computer programmers, if exposed to Chinese, would really admire its clarity and simplicity. It's like the Lisp of natural languages.
Egad, no! English is like Perl. It looks strange, but it's actually pretty simple and flexible, despite the ideas held in place with duct tape. Right->{}?
C++ is absurdly obtuse and complicated, for no good reason. It's not simple or flexible at all. If it were a natural language, it would be dead already. Native speakers would have been conquered by another people who could actually understand each other relatively unambiguously. Like English speakers.
Is ambiguity in language always a bad thing? William Empson wrote in Seven Type of Ambiguity that "The machinations of ambiguity are among the very roots of poetry", and he seemed to know a thing or two.